INSTRUCTIONS:
Enter a temperature with the
slidebar at the bottom and click
"New" to plot a Planck radiation
function. "Wien Law" illustrates
Wien's law for this temperature,
"SB Law" illustrates the Steffan-
Boltzmann Law, "B-V" calculates
the blue-visual color index, and
"U-B" calculates the UV-blue
color index. Enter a new T by
moving the slidebar and clicking
on "New". "Regions" chooses if
divisions of the spectrum are
displayed in the Planck Law plot.
Color indices are only approximate because intensities
are being evaluated at a single point corresponding to the
maximum transmission of the filter. In reality, the filters
have an acceptance width of about 1000 angstroms and a
skewed gaussian shape. Thus a correct calculation would
integrate with these acceptances as weights. Nevertheless
the color indices calculated with the simple method are
approximately correct.
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